Electrolytes Basic Must Knows Flashcards
Predominant CATION in the extracellular fluid
Sodium
“Potassium In, Sodium Out” - Extacellular –> Out
Electrolyte responsible for DNA replication
Magnesium
Electrolyte used for ATP production
Magnesium, Phosphate
Sodium is 99% reabsorbed by the renal tubules, influced by what hormone?
Aldosterone
This hormone blocks secretion of both aldosterone and renin
Atrial Natriuretic Factor
The most common electrolyte disorder
Hyponatremia
For every ______ increase in blood glucose, there is a decrease by _______ mmol/L of serum sodium
For every 100mg/dL increase in blood glucose, there is a decrease by 1.6 mmol/L of serum sodium
Methods of determination for Sodium
- FEP (Yellow)
- ISE - glass aluminum silicate
- AAS
- Colorimetry - albanese-lein
Reference and Panic Value for Sodium
RV: 135-145 mmol/L
PV: <120mmol/L
Major Intracellular Cation
Potassium
Major difference in function of sodium and potassium
- Sodium - for regulation of serum osmolality
- Potassium - for regulation of intracellular volume and H+ concentration; contraction of heart and excitibility of muscles
Decreased serum osmolality = increased sodium loss
Classify Addison’s disease for potassium and sodium levels
Hyponatremia
Hyperkalemia
Classify diabetic acidosis’ sodium levels
Hyponatremia
Classify severe dehydration’s sodium levels
Hypernatremia
Describe the acid-base balance influence of potassium in the body
Acidosis - favors K efflux
Alkalosis - favors K influx
Hormones that influences intracellular shifting of Potassium
Insulin, Cathecolamines, Aldosterone
Potassium reference value
3.5 to 5.1 mmol/L
Methods used for potassium determination
- FEP (Violet)
- ISE - valinomycin gel
- AAS
- Colorimetry - Lockhead-Purcell
Classify Cushing’s disease sodium and potassium levels
Hypernatremia
Hypokalemia
At what levels do weakness, fatigue, constipation appear with hypokalemia?
Below 3 mmol/L
Most abundant cation in the body
Third most abundant in the blood
Calcium
Most abundant extracellular anion cation
Anion = Chloride
Cation = Sodium
The only ion that serves as an enzyme activator
Chloride
Used for diagnosis of cystic fibrosis
Sweat chloride
Method for determination for Calcium
- Schales and Scahles - Mercurimetric Method
- Cotlove - coloumetric amperometric titration
- ISE - electrodes with AgCl membranes
Does PTH increase or decrease by:
* stimulating release of calcium from bones
* stimulating reabsorption of calcium
* increase absorption of calcium
Increase
Does calcitonin increase or decrease plasma calcium concentration?
Decrease
By stimulating uptake of calcium by bones and increase calcium excr
Two forms of calcium in plasma
- Protein-Bound - 80% to albumin, 20% to globulin
- Free calcium - with citrates, bicarbonates
Calcium methods of determination
- AAS - Reference Method
- ISE -liquid membrane, to measure ionized calcium
- Dye-binding
- Clark-Collip Precipitation - purple end point
- Ferro-Ham Chloronilic Acid - react with EDTA
4th most abundant cation and 2nd most abundant intracellular ion
Magnesium
Most affected by hemolysis
- Potassium
- Magnesium
This electrolyte is used as a therapeutic agent (anti-convulsant, laxative, antacid effects) and can be obtained from dietary sources such as nuts, vegetables, etc.
Magnesium
Only ion that serves as an enzyme activator
Chloride
Major intracellular anion used to maintain pH of body fluids and an important constituent of bones
Phosphate
Enumerate anion gap formulas and their reference values
- Na - (Cl + HC03): 7-16 mmol/L
- (Na + K) - (Cl + HCO3): 10-20 mmol/L
Electrolytes responsible for Acid-Base Balance
HCO3, K, Cl
Electrolytes responsible for blood coagulation
Calcium, Magnesium
Cofactors in enzyme activation
Mg, Ca, Zn
Electrolytes for myocardial rhythm and contractility
K, Mg, Ca
Production and use of ATP from glucose
Mg, PO4
Regulation of ATPase pumps
Mg
Volume and osmotic regulation
Na, K, Cl
